Vibration

[1997flht]

I've been chasing this vibration on my 1997 flht since last summer, it vibrates my left mirror and hand grip, its a high speed/buzz, worse at higher speed.  It seems to get worse the hotter it gets. I've changed the front motor mount [installed not upside down], changed clutch drum to latter style, installed hydrolic primary chain adjuster. If I pull the clutch in the vibe's go away. Normally this wouldn't bother me, but I just had my left knee replaced in December and I don't think the vibe's are good for my knee. Any ideas appreciated...enjoy the day, Thanks

[vern]

the rear swing arm bushing will wear out after a while, you can check by prying between the frame and outer cup, if there is any movement this could be where you vib is coming from. vern

[1997flht]

Thanks for the reply Vern, If I pry between the center bolt and the frame on the right side I can move the center bolt about 1/8 inch, but on the left side I can get about 1/4 inch movement. This bike only has 24,000 miles on it, would you say the bushing are bad with that kind of movement...thanks again

[Evo160K]

Have someone competent pull the primary cover and check the clutch hub bearing.  Might also have the lifters checked at the same time.

[baldoldfxr]

If you haven't already done so then check all the engine mounting & engine to gearbox bolts plus look very closely at the tie rods, the fact it goes away when the clutch is in points to the motor/gearbox being the cause rather than the cycle parts,
maybe woth checking the engine alignment in the frame as well. you say its been happening since last summer did anything get changed about then ?, somtimes the simple things get overlooked.

[vern]

with only 24.000 miles you wouldn't think the swing arm bushings would be worn out but that's a lot of play, maybe i'm wrong and it could be the clutch. but i've been chasing a vibration in my 96 dyna (different system than yours) for a season and it turnd out to be the rear rubber mount, some thing the HD dealer said never wears out. if your swing arm caps hit the frame or rub on the frame you will get a vib. vern

[stroker800]

  if it goes away with clutch pulled in,,,I would be thinkin its not motor, wheels..I would check main shafton tranny and alignment on drive...I often wonder myself how well balanced clutch baskets are,,,also check all bolts.
Dave

[customrdr]

 I had a bent primary shaft that caused vibration. Pull in clutch and the vibration stoped.To check, pull outer primary off, make sure rear tire is off ground or floor, put transmission in nurtrel. Turn primary shaft and notice if primary chain, or belt moves up and down(tighter or looser), if it does then you have a bent shaft.I bent my shaft by putting it in first gear without the clutch. That sudden jerk is not any good. I have done it to two of my bikes.

[1997flht]

Thanks for the reply....when you say primary shaft, do you mean the transmission mainshaft that the clutch basket sits on....have a great holiday

[vern]

i feel terrible that i might have sent you in the wrong direction about your vibe, but it's hard to diagnosis a problem over the internet. all you can do is try some diff suggestions and see what comes of it. if you find the answer or problem please let me know. good luck. Vern

[7ender]

You've changed the stock chain tensioner in the primary for an hydraulic type ,....could it be possible that the spring tension is to high ,...the plunger must be adjusted at the middle of the stroke ( f.i :  if the total stroke is 6 mm ,....you can place a 3mm drill under the nylon shoe to adjust it )
I've had vibration-problems as well , after I replaced my chain tensioner the hydraulic type , which I had wrong adjusted.

[lengbyroadking]

I know this sounds crazy, but did you replace the front mount with an aftermarket? After 3 months and $800 in labor I found the same vibe to be the new aftermarket mount I had installed on the front. After replacing it with OEM, the vibe was gone. Tried to save a few buck but found that the aftermarket mount was made of too soft of rubber to absorb the vibration.

[1997flht]

Thanks again for all the replies, I've tried readjusting the hydrolic tensioner a few times, same vibes....if I'm rolling down a grade at say 50mph I have a pretty good buzz/vibration in my floor boards and windshield, if I pull the clutch in or put it in neutral with the clutch out the vibes go away. I had the rear wheel off the ground the other day and had it up to about 40mph and I could really feel the vibes touching the tranny case, so I'm thinking I have a bent main shaft. After talking the tech dept. at Andrews the tech informed me that even if the engine kicks back against the starter while starting it's enough to bend the main shaft. Long story short I ordered a main shaft and bearings for my trans, just waiting for a rainy day to pull it apart. Anyone have any tips or things to watch out for while I'm changing the main shaft. Enjoy the day